Daniele Vergara

Epithelial–mesenchymal transition in ovarian cancer

Ovarian cancer is a highly metastatic disease and the leading cause of death from gynecologic malignancy. Hence, and understanding of the molecular changes associated with ovarian cancer metastasis could lead to the identification of targets for novel therapeutic interventions. The conversion of an epithelial cell to a mesenchymal cell plays a key role both in the embryonic development and cancer invasion and metastasis. Cells undergoing epithelial-mesenchymal transition (EMT) lose their epithelial morphology, reorganize their cytoskeleton and acquire a motile phenotype through the up- and down-regulation of several molecules including tight and adherent junctions proteins and mesenchymal markers. EMT is believed to be governed by signals from the neoplastic microenvironment including a variety of cytokines and growth factors. In ovarian cancer EMT is induced by transforming growth factor-beta (TGF-beta), epidermal growth factor (EGF), hepatocyte growth factor (HGF) and endothelin-1 (ET-1). Alterations in these cellular pathways candidate them as useful target for ovarian cancer treatment.

MALDI Imaging Mass Spectrometry STATE OF THE ART TECHNOLOGY IN CLINICAL PROTEOMICS

A decade after its inception, MALDI imaging mass spectrometry has become a unique technique in the proteomics arsenal for biomarker hunting in a variety of diseases. At this stage of development, it is important to ask whether we can consider this technique to be sufficiently developed for routine use in a clinical setting or an indispensable technology used in translational research. In this report, we consider the contributions of MALDI imaging mass spectrometry and profiling technologies to clinical studies. In addition, we outline new directions that are required to align these technologies with the objectives of clinical proteomics, including: 1) diagnosis based on profile signatures that complement histopathology, 2) early detection of disease, 3) selection of therapeutic combinations based on the individual patients entire disease-specific protein network, 4) real time assessment of therapeutic efficacy and toxicity, 5) rational redirection of therapy based on changes in the diseased protein network that are associated with drug resistance, and 6) combinatorial therapy in which the signaling pathway itself is viewed as the target rather than any single “node” in the pathway.

Drug-loaded polyelectrolyte microcapsules for sustained targeting of cancer cells ☆

In this review we will overview novel nanotechnological nanocarrier systems for cancer therapy focusing on recent development in polyelectrolyte capsules for targeted delivery of antineoplastic drugs against cancer cells. Biodegradable polyelectrolyte microcapsules (PMCs) are supramolecular assemblies of particular interest for therapeutic purposes, as they can be enzymatically degraded into viable cells, under physiological conditions. Incorporation of small bioactive molecules into nano-to-microscale delivery systems may increase drugs bioavailability and therapeutic efficacy at single cell level giving desirable targeted therapy. Layer-by-layer (LbL) self-assembled PMCs are efficient microcarriers that maximize drugs exposure enhancing antitumor activity of neoplastic drug in cancer cells. They can be envisaged as novel multifunctional carriers for resistant or relapsed patients or for reducing dose escalation in clinical settings.

Age-related pelvic floor modifications and prolapse risk factors in postmenopausal women

Objective: Genital prolapse is frequent in postmenopausal women; it describes the loss of support to the pelvic organs, resulting in a herniation of these into the vaginal channel. This problem affects 50% of parous women, and at least 50% of all women develop a mild form of genital prolapse after pregnancy. Methods: An extensive literature review from 1990 to 2008 was performed on prolapse etiology and its risk factors; analyzing the data, we reviewed the genetic and biological aspects, age-related prolapse, biological tissue modifications, surgical problems, pelvic musculature modifications, and neuropathy. Results: Data suggested that aging, pelvic trauma, and surgery evoke tissue denervation and devascularization, anatomic alterations, and increased degradation of collagen; all of these may lead to a decrease in mechanical strength and predispose an individual to prolapse. It has been demonstrated that there is a reduction in protein content and estrogens in uterosacral ligaments, in the vagina, and in the parametrium of women with prolapse. This is a possible explanation for why many surgical procedures to correct prolapse fail and recurrences after surgical correction are frequent. Conclusions: Even if the etiology of pelvic prolapse is poorly defined and multifactorial, aging risk factors, such as biomechanical abnormalities in connective tissue composition, hormonal deficiency, and irregular tissue metabolism, are nonmodifiable and therefore largely stated in clinical practice. Regardless of future developments, based on the reported findings, prolapse therapy will be more influenced by genetics, biological pelvic changes, changes in tissue homeostasis, and topical hormones, rather than general pelvic corrective surgical anatomy.

Resveratrol inhibits the epidermal growth factor-induced epithelial mesenchymal transition in MCF-7 cells

Carcinoma progression is associated with the loss of epithelial features, and the acquisition of a mesenchymal phenotype by tumour cells. Herein we show that exposure of MCF-7 cells to epidermal growth factor (EGF) resulted in morphological alterations characteristic of epithelial-to-mesenchymal transition (EMT). EGF treatment resulted in increased motility along with an up-regulation of transcription factors Slug, Zeb1, Zeb2, and mesenchymal markers Vimentin and N-cadherin. Treatment of MCF-7 cells with a combined stimulation of EGF and resveratrol, a naturally occurring stilbene with antitumor properties, failed to alter cell morphology, motility and overexpression of EMT markers induced by EGF. Using specific chemical inhibitors, we demonstrated that EGF-induced EMT is mediated by extracellular signal-regulated kinase 1/2 (ERK 1/2) signalling pathway and that resveratrol is able to repress EGF-induced ERK activation. In summary, these data provide new evidence of the inhibitory effect of resveratrol on EGF-induced EMT cell transformation.

Lapatinib/Paclitaxel polyelectrolyte nanocapsules for overcoming multidrug resistance in ovarian cancer.

The sonication-assisted layer-by-layer (SLBL) technology was developed to combine necessary factors for an efficient drug-delivery system: (i) control of nanocolloid size within 100 - 300 nm, (ii) high drug content (70% wt), (iii) shell biocompatibility and biodegradability, (iv) sustained controlled release, and (v) multidrug-loaded system. Stable nanocolloids of Paclitaxel (PTX) and lapatinib were prepared by the SLBL method. In a multidrug-resistant (MDR) ovarian cancer cell line, OVCAR-3, lapatinib/PTX nanocolloids mediated an enhanced cell growth inhibition in comparison with the PTX-only treatment. A series of in vitro cell assays were used to test the efficacy of these formulations. The small size and functional versatility of these nanoparticles, combined with their ability to incorporate various drugs, indicates that lapatinib/PTX nanocolloids may have in vivo therapeutic applications.

Resveratrol downregulates Akt/GSK and ERK signalling pathways in OVCAR-3 ovarian cancer cells

Phytochemicals constitute a heterogeneous group of substances with an evident role in human health. Their properties on cancer initiation, promotion and progression are well documented. Particular attention is now devoted to better understand the molecular basis of their anticancer action. In the present work, we studied the effect of resveratrol on the ovarian cancer cell line OVCAR-3 by a proteomic approach. Our findings demonstrate that resveratrol down-regulates the protein cyclin D1 and, in a concentration dependent manner, the phosphorylation levels of protein kinase B (Akt) and glycogen synthase kinase-3β (GSK-3β). The dephosphorylation of these kinases could be responsible for the decreased cyclin D1 levels observed after treatment. We also showed that resveratrol reduces phosphorylation levels of the extracellular signal-regulated kinase (ERK) 1/2. Chemical inhibitors of phosphatidylinositol 3-kinase (PI3K) and ERK both increased the in vitro therapeutic efficacy of resveratrol. Moreover, resveratrol had an inhibitory effect on the AKT phosphorylation in cultured cells derived from the ascites of ovarian cancer patients and in a panel of human cancer cell lines. Thus, resveratrol shows antitumor activity in human ovarian cancer cell lines targeting signalling pathway involved in cell proliferation and drug-resistance.

Cytomechanical and topological investigation of MCF-7 cells by scanning force microscopy.

Despite enormous advances in breast cancer biology, there is an increased demand for new technologies/methods that are able to provide supplementary information to genomics and proteomics. Here, we exploit scanning force microscopy (SFM) in combination with confocal microscopy, to investigate the morphological and mechanical properties of two neoplastic cell lines: (i) MCF-7 (human breast cancer) and (ii) HeLa (human cervical carcinoma). Living and fixed cells either in phosphate buffer solution (PBS) or in air have been studied, and the viscoelastic properties (including the Youngs modulus) of cells grown onto standard and modified (e.g. by fibronectin, one of the cellular matrix components) substrates have been measured. We observed different Youngs modulus values, influenced by the adhesion and growth behaviour onto specific substrate surfaces.

Effects of visceral peritoneal closure on scar formation at cesarean delivery

To determine the effect of closure or non‐closure of the visceral peritoneum at cesarean delivery on uterine scar formation assessed at repeat cesarean delivery.

MYOMA PSEUDOCAPSULE: A DISTINCT ENDOCRINO-ANATOMICAL ENTITY IN GYNECOLOGICAL SURGERY

Background. The myoma pseudocapsule is a structure formed surrounding the uterine fibroid, that in the uterus separates the myoma from normal tissue; because literature is lack of detailed information concerning myoma pseudocapsule, the author reviewed this important topic. Methods. An extensive literature review from 1980 to 2008 was performed on the myoma pseudocapsule, using: fibroid, myoma, myomectomy and reproductive outcome, as keywords. Results. The fibroid removal should always be performed inside its pseudocapsule and with a careful stretching, to extract fibroid from the surrounding fibromuscular skeleton, breaking up the fibrous bridges; because the vascular network generally surrounds the myoma, detachment of the myoma occurring inside the pseudocapsule should cause less bleeding. The maintenance of myometrial integrity during myomectomy allows the facilitation of uterine healing and is of benefit for future reproductive outcome. Conclusion. The benefits of intracapsular myomectomy are evident, because it preserves myometrial integrity and allows for restoration of the uterine musculature. This correct myomectomy, if done by laparoscopy, confers significant advantages in less intraoperative blood loss, short duration of hospital stay, few therapeutic antibiotic administration and better future fertility.